Atrio-ventricular nodal re-entrant tachycardia ablation step by step low fluoro approach to prevent unexpected AV block

Background

Slow pathway (SP) radiofrequency (RF) ablation of AVNRT has a success rate of more than 98%, but up to 2% risk of unpredictable and frustrating AV node block despite the energy being delivered to the posterior aspect of Koch's Triangle (KT) which is far from the recorded His signal. A possible explanation is an atypical location of the AV node. KT pace-mapping (KTPM) has been demonstrated to be useful to recognize when AV is abnormally located in the mid or posteroseptal aspect of the KT. In these cases cryoablation would be the best choice because it is a well-established technique for the successful treatment of AVNRT with no complications reported but with a recurrence rate around 10% at long-term follow-up. Voltage bridge mapping (VBM) is a validated and effective technique in guiding cryoablation of AVNRT, with a complete acute success rate and no recurrences at mid-term follow-up.

Aim

To evaluate our low-fluoro step-by-step approach for AVNRT ablation including KTPM and VBM aiming to eliminate the risk of unpredictable AV node block.

Methods

The right atrium and coronary sinus electroanatomical mapping was done and diagnostic catheters were positioned at His and coronary sinus. After AVNRT diagnosis, 3D KTPM was performed. We developed it according to the “conventional” one in order to evaluate and visualize atypical AV node location during low-fluoro procedures. This was achieved by stimulating with the mapping catheter in the anteroseptal, posteroseptal and midseptal region respectively. Each point has been collected on 3D System measuring the interval between the stimulus to the His deflection (Fig. 1A–C). Voltage bridge-mapping was also performed, and both have been used as reference for SP RF ablation. If 3D KTPM showed a posterior extension of the AV node, then ablation was performed using cryo-energy aiming to reduce the risk of permanent AV node iatrogenic block.

Methods and results

71 consecutive patients (mean age 61.0±14.5 SD, 46% female) undergoing low-fluoro ablation of AVNRT by 3D mapping system. KTPM was achieved in all the patients. In the 67 (94.3%) pts who showed superoparaseptal location of the AV node RF ablation was successfully performed. In 4 (5.7%) pts with midseptal extension of the AV node (Fig. 1D) a voltage-bridge mapping guided cryo-ablation was successfully performed (Fig. 1E). The mean procedural time was 95±18 SD min. Mean fluoro time was zero. After a mean follow-up of 28.5±16.7 SD moths, neither recurrences nor complications were recorded.

Conclusion

This is the first study to show how a tailored low-fluoro AVNRT SP ablation approach including 3D-PM of KT and VBM could be helpful to eliminate the risk of unpredictable and frustrating AV block. Our preliminary results would possibly encourage larger cohort, multicenter studies.

Funding Acknowledgement

Type of funding sources: None.

Contamination of revision procedures in patients with adverse tissues reaction to metal on metal implant

OBJECTIVE

The aim of this study is to evaluate the incidence of infections in MoM total hip replacement revisions and to propose a therapeutic algorithm that can reduce the onset of this complication. Total hip arthroplasty is one of the most successful procedures performed annually in the world. As the population ages, the number of primary arthroplasty procedures performed each year is rising in conjunction with an increasing revision burden. Metal on Metal (MoM) total hip arthroplasties were reintroduced in over the last fifteen years to meet these needs, larger diameters, improved lubrication, better stability, increased ROM and wear properties of the bearing couple. These advantageous features have led to an exponential diffusion of MoM. Since over last decade, it has become evident that hip replacements with MoM bearing have significantly higher revision rates compared to those with Metal on Polyethylene. The common pathway for this failure mode appears to be increased wear or corrosion with excessive release of metal ions and nanoparticles. Complications such as elevated serum metal ion levels, aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) and pseudotumours have all been well documented, but recent studies suggest increased risk of infection with MoM bearing surfaces.

PATIENTS AND METHODS

We collect data from a cohort of 44 patients who underwent revision of total hip arthroplasty between 2014 and 2017 for the complication of MoM bearing. Studied by radiological images, blood tests, and intraoperative clinical status, part of the population was treated with one stage revision, while the other was treated with a two-stage revision.

RESULTS

Results showed a difference in the occurrence of infections in the two populations.

CONCLUSIONS

We consider it appropriate to perform two-stage revision in all case of failure of MoM replacement so as to allow to minimize the likelihood of infection in patients with damaged tissues by ALVAL, pseudotumour, and necrosis that could create an ideal environment for bacterial development.

Frequency and clinical correlates of bipolar features in acute coronary syndrome patients

Background:

Depression and acute coronary syndrome (ACS) are both extremely prevalent diseases. Studies aimed at evaluating whether depression is an independent risk factor for cardiac events provided no definitive results. In most of these studies, depression has been broadly defined with no differentiation between unipolar (MDD) versus bipolar forms (BD). The aim of this study was to evaluate the frequency of DSM-IV BD (bipolar I and bipolar II subtypes, cyclothymia), as well as temperamental or isolated bipolar features in a sample of 171 patients hospitalized for ACS. We also explored whether these psychopathological conditions were associated with some clinical characteristics of ACS.

Methods:

Patients with ACS admitted to three neighboring Cardiac Intensive Care Units (CICUs) in a 12-month continuative period of time were eligible for inclusion if they met the criteria for either acute myocardial infarct with or without ST-segment elevation or unstable angina, verified by standard ACS criteria. All patients underwent standardized cardiological and psychopathological evaluations.

Results:

Of the 171 ACS patients enrolled, 37 patients (21.7%) were found to have a DSM-IV mood disorder. Of these, 20 (11.7%) had bipolar type I or type II or cyclothymia, while 17 (10%) were the cases of MDD. Rapid mood switches ranged from 11% of ACS patients with no mood disorders, to 47% of those with MDD to 55% of those with BD. Linear regression analysis showed that a diagnosis of BD (p = .023), but not that of MDD (p = .721), was associated with a significant younger age at the index episode of ACS. A history of previous coronary events was more frequent in ACS patients with BD than in those with MDD.

Conclusions:

Our data indicate that bipolar features and diagnosis are frequent in ACS patients. Bipolar disorder has a negative impact on cardiac symptomatology. Further research in this area is warranted.

Low complication rates in Minimally Invasive Plate Osteosynthesis (MIPO) for proximal humeral fractures at 5 years of follow-up

INTRODUCTION

Purpose of this study was to analyse the medium term follow-up of minimally invasive plate osteosynthesis (MIPO) for proximal humeral fractures in terms of postoperative shoulder function, radiological outcome and complications.

METHODS

76 consecutive patients with unstable proximal humeral fractures were treated using locking plate with a minimally invasive antero-lateral approach in two surgical centers. Constant score and radiographic evaluation of 74 patients were available at mean follow up of 5 years (minimum 4 years).

RESULTS

Mean Constant score was 74 (range to 28-100). Results were comparable in the two centers. Younger patients registered significantly higher scores (p < 0.05). 20 patients (27%) developed complications. Subacromial impingement occurred in 16,2% of cases for varus malreduction (6,7%) and for too proximal plate positioning (9,5%). Primary screws perforation (2,7%), secondary perforation due to cut-out (1,4%), avascular necrosis (AVN) of humeral head (1,4%), partial resorption of greater tuberosity (2,7%), secondary displacement of the greater tuberosity (2,7%) and stiffness (2,7%) were observed.

DISCUSSION AND CONCLUSIONS

Even at a medium term follow-up, MIPO for proximal humeral fractures ensured good and reproducible results for most common pattern of fractures. Major complications were lower respect to open procedures, because of soft tissue, deltoid muscle and circumflex vessels sparing.

Control of Uremic Neuropathy by Equilibrium Peritoneal Dialysis

Motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNVC) and distal motor latencies times (DMLT) were evaluated both in upper and lower limbs in three groups of 15 patients of comparable age, treated respectively by extracorporeal dialysis (HD), continuous ambulatory peritoneal dialysis (CAPD) and combined peritoneal dialysis (CPD) for comparable sufficiently long periods. Moreover, MNCV was monitored longitudinally in two groups of patients shifted from CAPD to HD and vice versa. The results show a significant superiority of peritoneal dialysis and particularly of CAPD with respect to HD in controlling uremic neuropathy.

Diurnal preference, mood and the response to morning light in relation to polymorphisms in the human clock gene PER3

PER3 gene polymorphisms have been associated with differences in human sleep-wake phenotypes, and sensitivity to light. The aims of this study were to assess: i) the frequency of allelic variants at two PER3 polymorphic sites (rs57875989 length polymorphism: PER3 ⁴, PER3 ⁵; rs228697 SNP: PER3 ^C, PER3 ^G) in relation to sleep-wake timing; ii) the effect of morning light on behavioural/circadian variables in PER3 ⁴ /PER3 ⁴ and PER3 ⁵ /PER3 ⁵ homozygotes. 786 Caucasian subjects living in Northern Italy donated buccal DNA and completed diurnal preference, sleep quality/timing and sleepiness/mood questionnaires. 19 PER3 ⁴ /PER3 ⁴ and 11 PER3 ⁵ /PER3 ⁵ homozygotes underwent morning light administration, whilst monitoring sleep-wake patterns and the urinary 6-sulphatoxymelatonin (aMT6s) rhythm. No significant relationship was observed between the length polymorphism and diurnal preference. By contrast, a significant association was observed between the PER3 ^G variant and morningness (OR = 2.10), and between the PER3 ^G-PER3 ⁴ haplotype and morningness (OR = 2.19), for which a mechanistic hypothesis is suggested. No significant differences were observed in sleep timing/aMT6s rhythms between PER3 ⁵ /PER3 ⁵ and PER3 ⁴ /PER3 ⁴ subjects at baseline. After light administration, PER3 ⁴ /PER3 ⁴ subjects advanced their aMT6s acrophase (p < 0.05), and showed a trend of advanced sleep-wake timing. In conclusion, significant associations were observed between PER3 polymorphic variants/their combinations and both diurnal preference and the response to light.

Characteristics of Migraine in an Out-Patient Population Over 60 Years of Age

One hundred and sixty-three consecutive patients (129 females and 34 males) over 60 years of age attending the Headache Centre of the University of Perugia in the period January 2000-December 2001 were included in the study.

One hundred and fifty-two (93.3%) were affected by a primary headache disorder. According to the 1988 IHS Criteria, their prevailing attacks could be diagnosed as migraine without aura (MwoA) in 57.2% of cases ( n = 87) and as migraine with aura (MwA) in 11.8% of cases ( n = 18). Attacks both in MwoA and MwA were unilateral and of severe-to-moderate intensity in 45% and 50% of cases. Head pain was referred as pulsating by 56% and 38.9% of MwoA patients MwA patients, respectively. Aggravation with routine daily activities was present in 72.4% and 61.1% in MwoA and MwA patient groups. The most frequent accompanying symptoms were photophobia and phonophobia. Headache attacks were of shorter duration in MwA patients, but in 3.4% of MwoA patients attacks lasted between 2 and 4 h. Of patients affected by MwA, 55% referred, together with the typical attacks, symptoms of aura not followed by headache. A worsening of headache in the last 5 years was reported by 67.8% and 44.4% of MwoA and MwA patients, respectively. Of the patients with MwoA, 86.2% ( n = 75), and 83.3% ( n = 15) of those with MwA used symptomatic drugs for their attacks. In the majority of cases they took more than one analgesic or non steroidal anti-inflammatory drug. A total of 51.7% of patients with MwoA and 55.5% of patients with MwA were under prophylactic treatment. Preventive drugs included antidepressants, beta-blockers, calcium channel antagonists and antiepileptic drugs. The choice of symptomatic or prophylactic drugs was made, in the majority of cases, on the basis of concomitant diseases.

Balance disorders in headache patients: evaluation by computerized static stabilometry

OBJECTIVES

The aim of the study was to investigate the occurrence of equilibrium disturbances in headache patients, during the interictal period, by computerized static stabilometry.

MATERIALS AND METHODS

Sixty-seven patients were studied: 35 with migraine without aura (MwoA), 12 with tension-type headache (TTH) in the episodic form (ETTH) + MwoA, and 20 with only TTH [10 ETTH + 10 chronic (CTTH)]. The stabilometric parameters considered were: statokinesigram length (L) and surface (S) in open (EO) and closed (EC) eyes conditions with/without occlusal bite, EC with head retroflexion (ECR), and optokinetic stimulation (OKN).

RESULTS

The alteration of at least one of the stabilometric parameters was observed in 45 patients (67.2%): 21 MwoA, 8 ETTH + MwoA, and 16 TTH (8 ETTH + 8 CTTH).

CONCLUSION

In TTH patients (ETTH, CTTH, ETTH + MwoA), the stabilometric findings show a proprioceptive alteration induced by cervicofacial muscle contraction, which was peripheral in origin. In MwoA patients the alterations appear under OKN and support a control impairment in involuntary oculomotility of central origin.

Headache characteristics in obstructive sleep apnea syndrome and insomnia

OBJECTIVES

To determine headache characteristics in the obstructive sleep apnea syndrome (OSAS) and in insomnia.

PATIENTS AND METHODS

Fifty-six OSAS patients and 50 insomnia patients were assessed in the same time period. Patients in both groups underwent an accurate interview to investigate headache occurrence and its characteristics. Results - Headache was reported by 49% of OSAS patients and 48% of insomnia patients. In OSAS patients headache had most frequently a tension-type pattern. Headache occurred on awakening in 74% of OSAS patients, more frequently than in insomnia patients (40%) (chi(2); P < 0.04). The occurrence of morning headache appears to be significantly correlated with nocturnal oxygen desaturation and OSAS severity.

CONCLUSION

Headache is a common finding in both OSAS and insomnia patients. Because morning headache seems to be more specific for OSAS than insomnia, and in OSAS its occurrence seems to be associated with disease severity, we hypothesize the involvement of certain pathogenic mechanisms associated with OSAS.

The role of neuroimaging in the diagnosis of headache in childhood and adolescence: a multicentre study

Following the diagnostic indications of the Guidelines for the diagnosis and therapy of juvenile headache, we present the results of a prospective, multicentre study of headache patients aimed at evaluating the utility of neuroradiologic testing in the diagnosis of headache. A total of 6535 subjects up to age 18 were studied, and 1485 underwent neuroimaging testing based on the indications of the diagnostic Flow-Chart. Abnormal results were observed in 273 (18.5%) subjects. Incidental findings were observed in 138 (9.3%) subjects, not correlated with the headache pathology, whereas alterations that led to the diagnosis of secondary headache were observed in 135 (9.1%) subjects. In conclusion, our data support a greater incidence of positive neuroimaging examinations among patients who underwent testing based on suspicion of a secondary headache pathology when compared with the low percentages observed in study populations.

Different cytokine levels in thrombolysis patients as predictors for clinical outcome

Thrombolytic therapy not always improves clinical outcome in ischemic stroke patients. This could cause lymphomonocyte accumulation in the infarcted brain area. These produce an excessive amount of proinflammatory cytokines, such as IL-1 beta, IL-6 and TNF-alfa. The aim of our study was to determine ILs levels in fibrinolytic therapy treated patients, compared with healthy controls and to evaluate if the varying levels can predictors of neurological outcome. Eighteen patients underwent thrombolytic treatment with t-PA within 3 h. Plasma levels of IL-1 beta, IL-6, TNF-alfa and IL-10 were determined by ELISA method before and within 24 h after t-PA infusion and compared with controls. Significantly higher levels of IL-1 beta and Il-6 emerged in stroke patients before treatment compared with the control group (P < 0.05 and 0.04, respectively). Slightly higher plasma levels of TNF-alfa and lower plasma levels of IL-10 were also found at base line in stroke patients. After thrombolytic treatment no significant variations were observed in the levels of TNF-alfa and IL-6, whereas a trend toward lower values for IL-1 beta and higher levels for IL-10 was observed. Positive correlations among the values of IL-6, TNF-alfa and National Institute of Health Stroke Scale (NIHSS) at discharges were observed. A similar correlation with modified Rankin scale score at 3 month was found. Pre-treatment cytokine status seems to influence pre-and long-term clinical outcome. Therefore an investigation into the possible predictor of cytokines seem worthy.

[Exercise test after acute myocardial infarction: on medical therapy?]

Given the great relevance of beta-blockers after myocardial infarction, we focused our attention on this therapy, considering also the difficulty of its management: it takes a long time to up titrate as well as to wash out. Other anti-ischemic therapies, i.e. nitroderivatives and calcium-antagonists, are easier to manage and there is less need of precise schedules. Our belief is that predischarge exercise testing should be performed on beta-blocker therapy, since we deem unadvisable to interrupt this treatment in the early phase of the postinfarction clinical course, and the reasons are detailed in the text. After myocardial infarction, beta-blockers may reduce the sensitivity of predischarge exercise testing for the diagnosis of inducible ischemia; however, their interference does not seem to affect negatively the prognostic stratification of the test, also in the "thrombolytic era". This may be true since beta-blockers hide, but also cure, those forms of inducible ischemia of lower clinical importance, and only inducible ischemia occurring in spite of such therapy might be dangerous and should be treated with myocardial revascularization. Patients receiving thrombolytic treatment are a selected minority at lower clinical risk; it is necessary to emphasize that predischarge exercise testing is more frequently positive in these patients, probably because of the presence of residual stenosis of the infarct-related vessel that may often have a trivial relevance. The test has a lower negative predictive value in these patients, mainly for the higher incidence of reinfarction and ischemic events related to plaque instability, events that none of the provocative tests can predict accurately.

Light-dependent interaction between Drosophila CRY and the clock protein PER mediated by the carboxy terminus of CRY

BACKGROUND

The biological clock synchronizes the organism with the environment, responding to changes in light and temperature. Drosophila CRYPTOCHROME (CRY), a putative circadian photoreceptor, has previously been reported to interact with the clock protein TIMELESS (TIM) in a light-dependent manner. Although TIM dimerizes with PERIOD (PER), no association between CRY and PER has previously been revealed, and aspects of the light dependence of the TIM/CRY interaction are still unclear.

RESULTS

Behavioral analysis of double mutants of per and cry suggested a genetic interaction between the two loci. To investigate whether this was reflected in a physical interaction, we employed a yeast-two-hybrid system that revealed a dimerization between PER and CRY. This was further supported by a coimmunoprecipitation assay in tissue culture cells. We also show that the light-dependent nuclear interactions of PER and TIM with CRY require the C terminus of CRY and may involve a trans-acting repressor.

CONCLUSIONS

This study shows that, as in mammals, Drosophila CRY interacts with PER, and, as in plants, the C terminus of CRY is involved in mediating light responses. A model for the light dependence of CRY is discussed.

Efficient and heritable functional knock-out of an adult phenotype in Drosophila using a GAL4-driven hairpin RNA incorporating a heterologous spacer

We have developed a modified RNA interference (RNAi) method for generating gene knock-outs in Drosophila melanogaster. We used the sequence of the yellow (y) locus to construct an inverted repeat that will form a double-stranded hairpin structure (y-IR) that is under the control of the upstream activating sequence (UAS) of the yeast transcriptional activator GAL4. Hairpins are extremely difficult to manipulate in Escherichia coli, so our method makes use of a heterologous 330 bp spacer encoding sequences from green fluorescent protein to facilitate the cloning steps. When the UAS-y-IR hairpin is expressed under the control of different promoter-GAL4 fusions, a high frequency of y pigment phenocopies is obtained in adults. Consequently this method for producing gene knock-outs has several advantages over previous methods in that it is applicable to any gene within the fly genome, greatly facilitates cloning of the hairpin, can be used if required with GAL4 drivers to avoid lethality or to induce RNAi in a specific developmental stage and/or tissue, is useful for generating knock-outs of adult phenotypes as reported here and, finally, the system can be manipulated to investigate the trans-acting factors that are involved in the RNAi mechanism.

Event-related potentials in posttraumatic headache

OBJECTIVES

To assess impairment of cognitive functions occurring in patients with posttraumatic headache as a consequence of a minor cranial trauma in the absence of organic damage involving the central nervous system.

BACKGROUND

The term posttraumatic syndrome defines a stereotypic set of symptoms following traumatic brain injury that are subjective and varied. A deficit of cognitive function and impairment of the rapid processes of learning, attention, and short-term memory have frequently been identified. Moreover, headache is the most frequent symptom reported by the patients. Due to the nature of the symptoms, a great limitation in defining the posttraumatic syndrome is represented by the lack of methods and diagnostic tools that allow quantification of the subjective disturbances and evidence of the signs indicative of central nervous system involvement in this pathological condition.

METHODS

Twenty-five subjects (16 women, 9 men; mean age, 28 +/- 9 years) were examined between 3 and 6 months after the traumatic event. The P300 event-related potential was recorded by an odd-ball paradigm with an acoustic modality. The patients underwent electroencephalography and brain stem auditory evoked potentials; magnetic resonance imaging was performed to exclude the presence of cerebral lesions.

RESULTS

The mean latency of P300 was increased in both central electrodes (Cz and Pz) in patients with posttraumatic syndrome compared with controls (P<.001); assuming the value of mean +/- 2 SD was the cutoff point between normal and abnormal results, the P300 latency results were altered in 13 patients (52%). In the patient group, a significant correlation was demonstrated between Zung Depression Scale score and P3 and N2 wave latencies (r = 0.54, P <.004; r = 0.56, P<.003) and between Zung Anxiety Scale scores and P3 wave latencies (r = 0.46, P<.02).

CONCLUSIONS

These data suggest the usefulness of the P300 event-related potential in evaluating cognitive disturbances in patients affected by posttraumatic syndrome. Alteration of cognitive potential in such patients, even in the absence of lesions detectable by neuroimaging, indicate the functional impairment of specific cerebral areas that can occur after a traumatic event.

[From the great clinical studies to the management of the single patient. Medical therapy in the pre- and post-fibrinolytic era]

Medical therapy of myocardial infarction has changed over the last 30 years. The "lag phenomenon", i.e. the time lapsing from the appraisal of a new, relevant scientific evidence and its practical adoption, has been variable, and different from one treatment to another. It has been very short for GP IIb/IIIa receptor inhibitors in candidates for urgent coronary angioplasty after myocardial infarction, short for ACE inhibitors, and it has been also short for the decrease in the prescription of calcium channel inhibitors after controversial scientific evidence. This time lapse has been long for beta-blockers, that only now are used quite extensively in Italy: from less than 10% of hospitalized patients during the early '80s, to over 60% nowadays. This evolution of medical therapy has been progressive and continuous, has not been divided into two eras, and thrombolysis seems to have little to do with it. The extensive introduction of thrombolysis has simply divided patients with acute myocardial infarction into two subgroups, very different for clinical characteristics: candidates for this therapy, and "others". Candidates for thrombolysis have a much better prognosis, but for a "paradox effect" they have been studied much more than the others. Now, the bulk of publications concerning patients undergoing thrombolysis carries the risk of spreading the concept that myocardial infarction has changed. We do not think that this corresponds to reality. Probably, the concepts that have guided medical therapy have been very similar and unchanged over the years, and both medical and surgical plus coronary angioplasty therapies are today much more appropriately used than yesterday.

[Guidelines: some considerations on one of the cultural instruments on which the switch in the National Health System can be based]

In the last few years there has been an explosion of interest in guidelines, reflected in a vivid debate in the international literature. Guidelines for medical practice are not innovative tools, since their history began at least 20 years ago. They are produced with increasing frequency in North America, and similar developments are taking place in Europe. The concept of improving the quality of the services in the National Health System through the production and implementation of valid clinical guidelines has been recognized in Italy by the Ministry of Health, who introduced such a concept in the last reform of the law on the Sanitary Health System. Many international authors deem that clinical guidelines are a way to support effective clinical practice. If this still holds, and we believe it does, then we must ensure that these guidelines are effective. Also for the enthusiast, the entire process from the development to the dissemination, implementation, and evaluation is not an easy task. Guidelines should be written correctly by a multidisciplinary panel of experts, should be peer reviewed and updated. Guidelines should become the common field in which the four major parties of the sanitary "market" (a market far from ideal today) meet: the patient, the doctor, the manager, and the industry involved in medical technology. Guidelines should be disseminated and implemented: simply having evidence available does not necessarily mean that it will be used. Thus, the key question is not so much related to the acceptance of best practice, but the extent to which a guideline is cost-effective. In this review we have tried to discuss such points, taking into consideration all the steps, the discussions, the controversial points, and the unsolved questions which are smoldering under both the potential benefit of practice guidelines (also in the light of appropriateness of medical practice), and all the possible effects on clinical autonomy, health care costs, clinical practice satisfaction, legal implications, and conflicts of interest. It is crucial for medical associations, and indeed for all physicians, to take up this problem and constructively try to play an active part in the process, avoiding the possibility that controversial guidelines be imposed by the regulatory authorities.

Inactivation of six genes from chromosomes VII and XIV of Saccharomyces cerevisiae and basic phenotypic analysis of the mutant strains

Within the frame of the EUROFAN project, aimed at the functional analysis of the novel ORFs revealed by the systematic sequencing of the Saccharomyces cerevisiae genome, we have inactivated six ORFs encoding putative proteins with unknown function in the two S. cerevisiae strains FY1679 and W303-1B. Five ORFs are located on chromosome VII (YGR250c, YGR251w, YGR260w, YGR262c, YGR263c) and one on chromosome XIV (YNL234w). The genes have been inactivated in the FY1679 strain by a strategy that makes use of deletion cassettes containing the kanMX4 module, which confers resistance to geneticin to yeast cells, and short flanking regions homologous to the target locus (SFH). Tetrad dissection of heterozygous mutants and basic phenotypic analysis of the spores revealed that ORF YGR251w is an essential gene, while the disruption of YGR262c causes a severe slow-growth phenotype. Deletion of the remaining ORFs did not give rise to a detectable phenotype in the mutant strains. For each ORF we have cloned, in the pUG7 plasmid, a replacement cassette that possesses long flanking regions homologous to the target locus (LFH) and, in the pRS416 plasmid, the cognate wild-type gene. The LFH replacement cassettes were used to inactivate the respective genes in the W303-1B strain. This work has been performed in the framework of the B0 Consortium of the EUROFAN I project.

[The evaluation of the appropriateness of instrumental exams in cardiology. The case of echocardiography]

BACKGROUND

The aim of this study was to evaluate the appropriateness and utility rates of echocardiograms performed in 309 patients in an outpatient clinical setting.

METHODS

Data were collected by means of a questionnaire filled in by the cardiologists who performed the examinations. Appropriateness was evaluated according to international guidelines and scored as class I: appropriate, class II: doubtful appropriateness, class III: inappropriate; the exam was deemed useful if it was able to influence the clinical decision-making; normalcy rate was also checked. The relationship between both the referring physicians and motivation of the exam and its appropriateness, and the relationship between appropriateness and both the normalcy rate and utility of the exam were assessed.

RESULTS

An echocardiogram was requested by the cardiologist in 46% of patients; the more common reasons for the exam were arterial hypertension (26%), cardiac murmur (18%), palpitations (15%), and known coronary artery disease (10%). The echocardiogram was appropriate (class I) in 25% of patients, doubtfully appropriate (class II) in 39% of patients and inappropriate (class III) in 36% of patients. The appropriateness rate between the cardiologists was similar to that of other prescribing clinicians (p = NS). The highest class III rate was found in patients with hypertension, while the highest class I rate was found in patients with a cardiac murmur (p < 0.01). Normalcy rate was lower in class I than in class II and III exams (p < 0.001). The utility rate was higher in class I (76%) than in class II (13%) and III (< 1%) exams (p < 0.01).

CONCLUSIONS

International guidelines can be used effectively and safely to identify (not to prescribe) the useless echocardiograms.

Outcome of juvenile headache in outpatients attending 23 Italian headache clinics. Italian Collaborative Study Group on Juvenile Headache (Società Italiana Neuropsichiatria Infantile [SINPI])

A multicenter 3-year follow-up study was carried out on young patients with headache referred to tertiary headache centers or pediatric clinics. Three years after the first examination in 1993, 442 (of an original sample of 719) young outpatients with headache (226 females and 216 males) were re-examined. The diagnostic criteria of the International Headache Society (IHS) and those modified for migraine without aura by Winner et al were applied at both the baseline evaluation and the 3-year re-examination. At the follow-up, 290 children still had headache, 101 were in clinical remission, and 51 had dropped out. Using the current diagnostic criteria, only 46.2% of patients having migraine without aura, 50% of those having migraine with aura, and 35.3% of those suffering from migraine disorders which do not fulfill IHS criteria for migraine received the same diagnosis at the time of follow-up. The percentage of patients receiving a diagnosis of migraine without aura rose significantly when new modified criteria were used (60.5%), whereas a drop in the frequency of migraine disorders not fulfilling IHS criteria was observed at follow-up, both in patients with the diagnosis of migraine without aura at the first examination (4.6%) and in patients with migraine not always fulfilling IHS criteria at the first examination (6.2%). Among all patients who received this latter diagnosis at the first examination, it was possible to make a diagnosis of migraine with aura at the follow-up in 8.8% of cases and that of migraine without aura in 26.5%. No significant variations in the frequency of either episodic tension-type headache or chronic tension-type headache were found, with the exception of a slight decrease in the percentage of tension-type headache which did not fulfill IHS criteria, but the difference between the first examination and the follow-up values does not reach the level of statistical significance (5% versus 12%). As far as the evolution of migraine is concerned, 17.4% of patients with migraine were headache-free at the 3-year follow-up. In tension-type headache, the percentage of patients who were headache-free was particularly high in those with the episodic form (32.9%) and in those suffering from tension-type headache not fulfilling IHS criteria (29.1%). The majority of patients who had been diagnosed as having unclassifiable headache at the first examination received a correct diagnosis at the follow-up with the exception of one patient. As observed in adult patients, variations in the headache characteristics were also observed in children and adolescents (that is, migraine with aura can change to migraine without aura, or the latter can transform into episodic tension-type headache or chronic tension-type headache can change into the episodic form). This follow-up study was aimed at reaching a better understanding of headache disturbances in children and adolescents, examining, in particular, variations of headache with time in this stage of life.

Intracellular Mg++ concentration and electromyographical ischemic test in juvenile headache

One-hundred-and-twenty-eight young headache outpatients underwent an electromyographical (EMG) ischemic test and determination of Mg++ levels in red and mononuclear blood cells. In migraine patients, with and without aura (MwA and MwoA), Mg++ concentration in the erythrocytes and in mononuclear cells was significantly reduced compared to tension-type headache (TTH) patients and healthy controls (p < 0.0001). The EMG ischemic test was positive in 71% of migraineurs, but only in 9.5% of TTH patients. Low intra-erythrocyte and mononuclear cell levels were evident in 84.3% and 81.2% of migraine patients, respectively; those whose ischemic tests were positive had intra-erythrocyte and mononuclear cell levels of Mg++ below the norm, respectively. However, reduced levels of Mg++ in erythrocytes were found in only two patients with TTH, and in mononuclear cells in one patient with TTH. These data provide further confirmation of the role of Mg++ in determining the status of neuromuscular hyperexcitability in about two-thirds of migraine patients, including childhood and adolescence. They also support the validity of carrying out EMG ischemic testing for distinguishing this condition, which can be corrected with adequate oral Mg++ supplementation and with a possible positive impact on headache.

[An economic assessment of the use of abciximab as a coronary angioplasty preparation in the Italian health-care context]

Drugs blocking platelet glycoprotein IIb/IIIa receptors (anti-GP IIb/IIIa) have been used effectively to prevent thrombotic events after percutaneous transluminal coronary angioplasty (PTCA). However, the high cost of these drugs calls for an economic evaluation before they can be used systematically within the context of the Italian health-care system.

METHODS

The systematic review of three studies (EPIC, EPILOG, CAPTURE) that evaluated the effectiveness of abciximab (the only anti-GP IIb/IIIa drug commercially available in Italy) demonstrated that this drug can prevent thrombotic events (death, myocardial infarction, repeated PTCA, bypass surgery) at six months after PTCA (RR 0.84; IC 95% 0.77-0.91; number needed to treat for the composite end-point 21). We performed an economic evaluation of the use of abciximab, taking into account the cost the drug (2,561,100 Italian lire [ITL]/patient) and the number of events prevented. We calculated the mean cost-effectiveness ratio (cost of each patient without events at six months after PTCA), the incremental cost-effectiveness ratio (cost of each event prevented at six months after PTCA) and the cost of each year of life saved at six months after PTCA.

RESULTS

The mean cost-effectiveness ratio was 16.6 million ITL/patient (versus 15.4 million ITL/patient without the use of the drug); the incremental cost-effectiveness ratio was 34.3 million ITL/event prevented; the cost of each year of life saved was 32.3 million ITL.

CONCLUSIONS

With abciximab preventing thrombotic events at six months after PTCA, the cost of each patient without events and the cost of each event prevented at six months are within the range of other pharmaceutical procedures in cardiology (e.g. thrombolysis in acute myocardial infarction with tissue plasminogen activator). Our analysis supports the case for the systematic use of abciximab in patients undergoing PTCA.

Characterization of a new hemoprotein in the yeast Saccharomyces cerevisiae

The Saccharomyces cerevisiae gene YNL234w encodes a 426-amino acid-long protein that shares significant similarities with the globin family. Compared with known globins from unicellular organisms, the Ynl234wp polypeptide is characterized by an unusual structure. In this protein, a central putative heme-binding domain of about 140 amino acids is flanked by two sequences of about 160 and 120 amino acids, respectively, which share no similarity with known polypeptides. Northern analysis indicates that YNL234w transcription is very low in cells grown under normal aerobic conditions but is induced by oxygen-limited growth conditions and by other stress conditions such as glucose repression, heat shock, osmotic stress, and nitrogen starvation. However, the deletion of the gene had no detectable effect on yeast growth. The Ynl234wp polypeptide has been expressed in Escherichia coli, and the hemoprotein nature of the recombinant protein was demonstrated by heme staining after SDS/polyacrylamide gel electrophoresis and spectroscopic analysis. Our data indicate that purified recombinant Ynl234wp possesses a noncovalently bound heme molecule that is predominantly found in a low spin form.

Pitfalls in the economic evaluation of thrombolysis in myocardial infarction. The impact of national differences in the cost of thrombolytics and of differences in the efficacy across patient subgroups

BACKGROUND

The economic evaluation of the results of the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Artery (GUSTO) trial found that recombinant tissue plasminogen activator is more cost-effective than streptokinase for the treatment of acute myocardial infarction.

AIM

We evaluated the impact on a cost effectiveness analysis, of the differences in the cost of thrombolytics among countries and of differences in efficacy across patient subgroups.

METHODS

We considered the crude costs of streptokinase and recombinant tissue plasminogen activator in Germany, Italy, the United Kingdom, and the United States of America, and the 30-day mortality found in the GUSTO trial. We calculated the incremental costs for each life saved when streptokinase is substituted by recombinant tissue plasminogen activator. We also calculated the incremental costs for each life saved for two protocols implying a selective use of streptokinase and recombinant tissue plasminogen activator (age-selective protocol: recombinant tissue plasminogen activator in patients < or = 75 years, streptokinase in older patients; site-selective protocol: recombinant tissue plasminogen activator in anterior acute myocardial infarction, streptokinase in non-anterior acute myocardial infarction).

RESULTS

The incremental costs for each life saved when streptokinase is substituted by recombinant tissue plasminogen activator in all GUSTO patients vary greatly among countries: the incremental costs for each life saved are 31%, 45%, and 97% higher in Germany, Italy, and the United States of America compared to the United Kingdom. The use of a site-selective protocol implies a halved cost-effectiveness ratio compared to the use of recombinant tissue plasminogen activator in all cases of acute myocardial infarction.

CONCLUSIONS

(1) The cost-efficacy of recombinant tissue plasminogen activator vs streptokinase in acute myocardial infarction varies greatly among countries due to differences in the cost of drugs. (2) A selective use of thrombolytics for some sites of infarction is more cost-effective than the exclusive use of recombinant tissue plasminogen activator.

Myocardial scintigraphy in acute myocardial infarction treated with systemic thrombolysis: how far are we from obtaining reliable information for rescue PTCA?

All noninvasive tests have an unsatisfactory accuracy in assessing patency of the infarct related vessel after systemic thrombolysis. In large infarctions, the prompt knowledge of the amount of jeopardized myocardium, as well as the eventual success of thrombolysis on the culprit lesion are major clinical needs in the subsequent decision making process, including the indication to rescue PTCA. Several reasons preclude a meaningful use of thallium scintigraphy in this setting: the most important one is the need to perform pre-thrombolytic images before the administration of the active agent, implying a delay in the administration of thrombolysis that is clinically not acceptable. SestaMIBI perfusion scintigraphy at rest seems more suitable in this regard. SestaMIBI practically does not redistribute in the myocardium, and this implies that after an administration at admission in the CCU, the pre-thrombolysis images can be acquired later, without any interference with the therapeutic schedule. The estimate of myocardial salvage can be obtained by the comparison of the perfusion pattern derived from a later sestaMIBI injection with the pre-lysis images. Both planar and tomographic reconstructions have satisfactory positive and negative predictive accuracy for the patency of the culprit vessel. Difficulties are related with the necessity of having this information timely; we describe a few protocols, appeared in the literature, that might contribute in solving such problems. SestaMIBI imaging in patients with acute myocardial infarction should be encouraged and extended, given its potential to represent one of the best tool to judge the amount of jeopardized myocardium, the obtained salvage, and to guide the decision making after systemic thrombolysis.

Relation between white blood cell count and several risk factors for coronary heart disease in patients with systemic hypertension

BACKGROUND

Several epidemiological studies have shown a relation between white blood cell (WBC) count in peripheral blood samples and other cardiovascular risk factors. Such associations have also been described in patients affected by dyslipidemia. On the other hand, no data are available in patients with systemic hypertension.

AIM

In a southern Italian population of hypertensive patients, in order to assess the relation between WBC count and other risk factors for coronary artery disease; in addition, to evaluate if a high WBC count can identify subgroups of hypertensives with a higher risk profile for atherosclerosis.

POPULATION AND METHODS

We evaluated 147 consecutive patients (44 males, mean age 49 +/- 11 years) with a minimum 2-year history of systemic hypertension in the absence of ischemic heart disease and cerebrovascular disease. Among risk factors, we considered: hypercholesterolemia, hypertriglyceridemia, hyperglycemia and obesity.

RESULTS

WBC count was significantly higher in patients with 2 or more risk factors (7.092 +/- 1034 cells/dl than in hypertensives without risk factors (5.902 +/- 1167, p < 0.0001). WBC count was significantly associated with hyperglycemia (p < 0.001), number of cigarettes smoked daily (p < 0.004), fibrinogen plasma levels (p < 0.008) and azotemia (p < 0.009). Multivariate analysis has shown a positive significant and independent relation between WBC count and both hyperglycemia and number of cigarettes.

CONCLUSIONS

These results emphasize that, among hypertensives, subgroups with a higher WBC count also have a higher risk profile for atherogenesis. The relation between WBC and some risk factors is confirmed by our data in a population of patients affected with systemic hypertension.

Study of pressure pain and cellular concentration of neurotransmitters related to nociception in episodic tension-type headache patients

The pressure pain threshold of 30 patients affected by tension-type headache was assessed and the values compared with those of a group of 30 age-matched control subjects. In the patient group, pressure pain threshold values were related to the blood cell concentration of some neurotransmitters which are considered to be involved in the genesis and modulation of pain (beta-endorphin levels in peripheral blood mononuclear cells [PBMCs], substance P and serotonin concentrations in platelets). The pressure pain threshold was significantly lower in tension-type headache patients than in control subjects (P < 0.0006). Significantly lower levels of beta-endorphins in PBMCs and substance P in platelets, as well as significantly higher levels of serotonin in platelets were found in tension-type headache patients compared to the control subjects (P < 0.0001). A significant positive correlation was found between pressure pain threshold values and beta-endorphin levels in both control and patient groups (P < 0.0001). On the contrary, a statistically significant negative correlation was evident between pressure pain threshold values and substance P levels in platelets in both patients and control subjects (P < 0.01 and P < 0.001, respectively). In both groups, there was a negative correlation between beta-endorphins in PBMCs and substance P in platelets (patients P < 0.02, controls P < 0.001). The findings of altered beta-endorphin levels in blood mononuclear cells and substance P levels in platelets could be the peripheral biochemical reflection of the low pressure pain threshold values in tension-type headache patients, and support the hypothesis of an impairment of the antinociceptive systems in this form of headache.

Desmopressin and imipramine in the management of nocturnal enuresis: a multicentre study

The efficacy and safety of desmopressin (Minirin/DDAVP) treatment compared with imipramine were investigated in a multicentre, open, cross-over design in 57 patients, aged 6-15 years, affected by nocturnal enuresis to establish the best therapeutic approach to this condition. After a two-weeks observation and control period, patients were randomised to one of two groups: intranasal administration of desmopressin, 30 micrograms/day for three weeks, followed by imipramine, 0.9 mg/kg for a further three weeks, or imipramine 0.9 mg/kg for three weeks, followed by desmopressin, 30 micrograms/day for a further three weeks. Following treatment, all patients were observed for a further two weeks. Administration of either treatment protocol resulted in a statistically significant decline in the number of enuretic episodes per week compared to the control. The greater antidiuretic effect observed in the group receiving imipramine followed by desmopressin suggests the two compounds have different profiles. Also, when the treatment period was compared with the follow-up, the antidiuretic effect had a longer duration in the group initially given imipramine. No further improvement was seen when desmopressin was administered first, with a mild worsening of the effect sometimes occurring, suggesting a different carry-over effect between the two treatments. This suggests that desmopressin offers a better approach to the management of nocturnal enuresis.

L-arginine/nitric oxide pathway activation in platelets of migraine patients with and without aura

Nitric oxide (NO) in platelets has been proposed as a promising tool for studying NO variations in migraine. In the present research the platelet response to collagen and the basal and collagen-induced production of NO and cGMP in platelet cytosol were assessed in migraine patients (25 with aura and 35 without aura) both interictally and ictally, and compared with the same parameters in 30 age-matched control subjects. A reduced responsiveness to collagen was found in migraine patients, particularly those with aura, and this was more marked during attacks (ANOVA interictal periods: p < 0.01, attacks: p < 0.02) The basal and collagen-stimulated production of NO and cGMP in the platelet cytosol was significantly higher in migraine patients with aura assessed in interictal periods than in control subjects, and this production was further increased during attacks (interictal period: NO ANOVA: p < 0.001, ictal period: p < 0.01; cGMP: interictal period p < 0.01, ictal period: p < 0.02). The increase in platelet NO and cGMP production was also evident, though to a lesser extent, in migraine patients without aura. The present research supports the hypothesis of an activation of the L-arginine/NO pathway in migraine patients, especially those with aura, and confirms the findings of a previous study of increased levels of L-arginine in platelets of migraine patients studied in headache free-periods, and decreased collagen aggregation in whole blood.

Electromyographical ischemic test and intracellular and extracellular magnesium concentration in migraine and tension-type headache patients

Headache has often been described in the hyperexcitability syndrome which recognizes an alteration of calcium and magnesium status in its etiopathogenesis. Moreover, in migraine patients magnesium has been shown to play an important role as a regulator of neuronal excitability and, therefore hypothetically, of headache. The present research involves a neurophysiological evaluation and magnesium status assessment of a group of headache patients. Nineteen patients (15 women and 4 men) with episodic tension-type headache and 30 patients (27 women and 3 men) with migraine without aura were examined. An ischemic test was carried out on the right arm with electromyographic (EMG) recording of motor unit potential activity during the interictal period. The determination of extracellular (serum and saliva) and intracellular (red and mononuclear blood cells) magnesium was also performed. The EMG test was positive in 25 of 30 migraine patients and in 2 of 19 tension-type headache patients. Between the two patient groups, there were no significant variations in the concentration of extracellular and white blood cell magnesium, while the red blood cell concentration of this mineral in the group of migraineurs was significantly reduced with respect to that in the group of tension-type headache patients (P < 0.05). The positive EMG test was significantly associated with a low concentration of red blood cell magnesium (P < 0.0001). These results confirm previous findings by demonstrating different etiopathogenic mechanisms as the basis of migraine and tension-type headache. Migraine seems to be related to an altered magnesium status, which manifests itself by a neuromuscular hyperexcitability and a reduced concentration in red blood cells.

[Efficacy and tolerability of felodipine and nifedipine in stable angina refractory to beta-blocker therapy]

BACKGROUND

Medical therapy of stable angina contemplates beta-blockers as a first line. The combination of dihydropyridines with beta-blocking drugs enhances the effectiveness of both single therapies. Nifedipine, in the usual formulation (AR), is burdened by an unsatisfactory tolerability, and this is the main reason to study new dihydropyridines.

AIM

To compare efficacy and tolerability of felodipine ER 10 mg o.d. with that of nifedipine AR 20 mg b.d. in patients with stable angina pectoris refractory to beta-blocker therapy.

PATIENTS AND METHODS

Of 15 initial patients, 14 were entirely evaluable for the study, the design of which was double blind, double dummy, random cross over and placebo controlled. All patients showed reproducible threshold of ischemia at exercise testing. In constancy of beta-blocker therapy, they were given placebos for 2 weeks, then one of the active drugs with a placebo of the other one for 4 weeks, followed by the cross-over period of 4 weeks. Efficacy and tolerability of treatments were evaluated by clinical observation and rest and exercise radionuclide angiography. At the end of each individual study, it was decided blindly if and which of the 2 drugs seemed preferable, considering symptoms, undesired collateral effects and the results of exercise procedures.

RESULTS

The efficacy on angina of the 2 active treatments was not different. More patients suffered undesired side effects on nifedipine than on felodipine. Left ventricular ejection fraction (LVEF) at rest was 65.3 +/- 4.3% (s.e.) on placebo, 64.6 +/- 2.6% on felodipine and 67.5 +/- 2.5% on nifedipine (p n.s.). A significant reduction in resting LV function (that is, a decrease of LVEF > or = 5%) was observed in 2 patients on felodipine and 3 on nifedipine, but in both groups other 3 patients showed improvement in LVEF. During exercise, LVEF decreased 6.1 +/- 2.0% on placebo and 3.3 +/- 3.2% on nifedipine, while it increased 1.0 +/- 2.6% on felodipine (p < 0.01 vs. placebo). At the end of the study, felodipine was blindly judged superior to nifedipine in 10 patients, nifedipine was superior in 1 case, in the other 3 there was no clear difference (p < 0.02).

CONCLUSIONS

In 14 patients with stable angina refractory to beta-blockers, the addition of felodipine or nifedipine has similar antiischemic effects. However, felodipine showed better results in LVEF response to exercise and less side effects, and this leaded to a more frequent blind choice of felodipine versus nifedipine to add to beta-blocker therapy.

Association between white blood cell count and risk factors of coronary artery disease

BACKGROUND

Epidemiologic studies have shown a correlation between white blood cell (WBC) count and risk of developing myocardial infarction. Aim of this study is to assess the association between WBC and the other risk factors of coronary heart disease in a southern Italian population.

METHODS

Baseline data for the 1091 subjects (522 males and 569 females) enrolled in the "Montecorvino Rovella Project" were used to study factors associated with leukocytes.

RESULTS

WBC count was significantly higher in smokers (8711.1 +/- 1892 cells/dl) than in ex-smokers (6720 +/- 1608 cells/dl) and in those who never smoked (6674 +/- 1608 cells/dl). By multiple linear regression analysis, WBC count showed a positive association with triglycerides (p < 0.01), cholesterol (p < 0.05) fasting glucose levels (p < 0.01) and diastolic blood pressure (p < 0.05).

CONCLUSIONS

In this southern Italian population, elevated WBC count has been associated with other risk factors of coronary artery disease, particularly smoking, and has identified a high risk atherogenic profile. Even if the independency of the role of WBC is still under investigation, WBC count should be taken into account in establishing the coronary risk of apparently healthy people.

Cognitive event-related potential in hepatic encephalopathy

A study of auditory P300 was performed on 24 patients with cirrhosis of the liver: 13 patients with hepatic encephalopathy (HE grade 1-2) and 11 patients without clinical encephalopathy (HE grade 0). The patients were also assessed using spontaneous EEG and neuropsychological methods: Mini Mental State, Digit Span and Number Connection Test. The P3 latency was found to be significantly increased in all patients (100%) with HE grade 1-2 and in 6 patients (54.5%) with HE grade 0. The clinical value of using the P300 latency in the hepatic encephalopathy is subsequently discussed.

The event-related potential P300 during headache-free period and spontaneous attack in adult headache sufferers

The event-related potential P300 has been studied in 15 migraine without aura sufferers, and in 15 episodic tension-type headache sufferers, during pain-free periods and during spontaneous headache attacks. There were no variations of potential, either of P3 latency or N2-P3 amplitude, in either group during the interictal period. Similarly, there were no variations of the P300 parameters in the group of tension-type headache subjects during headache attacks; by contrast, a significant elongation of latency (P < 0.01) and an increment of N2-P3 wave amplitude (P < 0.002) was observed in the group of migraineurs. The authors discuss the data in accordance with the etiopathogenic theories of migraine and the hypothesis that acetylcholine and norepinephrine are the neurotransmitter able to affect the event-related potential P300, which reflects cerebral activity during sensory information processing and analysis.

Risk stratification of patients with coronary artery disease and left ventricular dysfunction by exercise radionuclide angiography and exercise electrocardiography

BACKGROUND

The results of multicenter trials indicate that patients with left ventricular dysfunction and either three-vessel or left main coronary artery disease have improved prognosis when treated surgically.

OBJECTIVE

As part of a larger evaluation and follow-up study of coronary artery disease, the objective of this investigation was to determine whether exercise radionuclide angiography can be used, in patients with mild symptoms of coronary artery disease and left ventricular dysfunction at rest, to identify patients with three-vessel or left main coronary artery disease.

METHODS AND RESULTS

Eighty-four consecutive patients were studied with angiographically defined coronary artery disease in whom left ventricular ejection fraction at rest ranged from 20% to 40%. Patients underwent exercise electrocardiography, rest and exercise radionuclide angiography, and 24-hour electrocardiographic monitoring. There were 22 patients with one-vessel, 31 with two-vessel, 27 with three-vessel, and four with left main coronary artery disease. All but four patients had a documented history of myocardial infarction. By univariate analysis, the following parameters were related to the anatomic severity of coronary artery disease: magnitude of ST segment depression with exercise (p < 0.001), magnitude of change in ejection fraction with exercise (p < 0.005), and occurrence of angina during exercise (p < 0.005). However, because of the extensive overlap among anatomic subgroups, no single factor had both a satisfactory sensitivity and a satisfactory specificity in identifying patients with three-vessel and left main coronary artery disease. Multivariate stepwise regression analysis also failed to predict three-vessel or left main coronary artery disease satisfactorily (sensitivity 73% and specificity 73%; positive predictive accuracy 59% and negative predictive accuracy 83%). Nonetheless, this multivariate analysis provided important prognostic information. During medical therapy (mean follow-up 56 months), the patients with a high likelihood of three-vessel or left main coronary artery disease had a greater risk of death or reinfarction than had patients with a low likelihood (p < 0.05). These functional data were better than coronary anatomy alone in providing risk stratification. Four of six patients with two-vessel disease who died were classified incorrectly by the multivariate analysis in the high-likelihood group for three-vessel or left main coronary artery disease, but classified correctly as being at high risk; whereas none of the patients with three-vessel disease who were misclassified in the low-likelihood group died during medical therapy.

CONCLUSION

Although exercise radionuclide angiography in patients with minimal symptoms of coronary artery disease and left ventricular dysfunction is not precise in predicting three-vessel or left main coronary artery disease, it provides important functional information regarding subsequent prognosis during medical therapy.

Changes in auditory P3 event-related potentials in uremic patients undergoing haemodialysis

A study on event-related P300 potential (ERPs) was performed in 20 patients suffering from chronic uraemia and undergoing haemodialysis in order to assessing the functioning of their cognitive processes. The patients were evaluated before and after a standard treatment of haemodialysis. The P300 potential was studied by means of the "oddball" paradigm and the acoustic modality. Moreover the patients' performance was assessed on the basis of the following psychological tests: the Mini Mental Test, the Number Connection Test and the Digit Span of the Wechsler Adult Intelligence Scale. A significant improvement in the P3 latency was demonstrated following the dialysis treatment. Even though a slight improvement in the N2-P3 deflexion amplitude was recorded after dialysis, it was not statistically significant. These data indicate a positive modification in the speed of the cortical function as a consequence of dialysis. These results suggest that the P3 latency obtained from auditory stimuli can help to assess the benefits obtained through extracorporeal dialysis, especially in the follow-up to the illness.

Predicting severe ischemic events after uncomplicated myocardial infarction by exercise testing and rest and exercise radionuclide ventriculography

BACKGROUND

In 183 patients with uncomplicated myocardial infarction, exercise-induced angina, ST segment depression, decrease in ejection fraction, or inadequate increase in systolic blood pressure and low exercise tolerance were significantly associated with 4-year incidence of hard ischemic events.

METHODS AND RESULTS

Only the onset of both ST segment depression and a decrease in left ventricular ejection fraction with exercise was an independent predictor. ST segment depression and decrease in left ventricular ejection fraction had low sensitivity (61% and 70%) and specificity (56% and 51%) for hard ischemic events, but specificity increased to 78% when both were present. During medical therapy, 22 of 53 patients with both ST segment depression and a decrease in left ventricular ejection fraction with exercise had an ischemic event (i.e., 48.1% 4-year probability on Kaplan-Meier analysis vs 19.2% in the remaining 130 patients [p < 0.0005]).

CONCLUSIONS

Even if no single variable, derived from exercise testing, is a highly sensitive and specific predictor, specificity increases to a clinically relevant level by combining ST segment depression and a decrease in left ventricular ejection fraction with exercise, and in this way patients with recent infarction may be selected for coronary arteriography.

[Angiotensin converting enzyme inhibitors during acute phase of myocardial infarct]

Up to September, 1993, several questions were open on the use of angiotensin converting enzyme (ACE) inhibitors after myocardial infarction. The SAVE trial has shown that patients with left ventricular dysfunction and a recent (mean 11 days) myocardial infarction benefit from assuming captopril per os during the subsequent clinical course. The SOLVD trials have indicated that therapy with enalapril per os increases the survival of patients with left ventricular dysfunction, a history of myocardial infarction and hemodynamic decompensation. However, the CONSENSUS II trial has not shown similar results on patients with all range left ventricular function, treated within 24 hours of infarction with i.v. enalaprilat and then enalapril per os. In this study, 6-month mortality has been slightly better in the placebo group, and there seems not to be any subgroup benefitting from the ACE inhibitor. In October and November, 1993, the International Cardiologic Community has received the results of 3 large multicenter trials on postinfarction patients: the AIRE (ramipril per os), the GISSI 3 (lisinopril per os) and the ISIS 4 (captopril per os) studies. These trials has pointed out the followings: 1) prompt therapy (within 24 hours of chest pain) with ACE inhibitors is able to improve short term survival in patients with clinical evidence of heart failure, in women and old patients; 2) ACE inhibitors and nitro derivatives are complementary therapies in the acute and subacute phase of infarction, and their association produces the best improvement in short-term survival. There seems to be no intelligible reason, up to now, to deem that any ACE inhibitor should be considered better than another one in the acute phase of infarction, but still during the first 72 hours after the onset of chest pain the advantages have been shown only with lisinopril and captopril. The negative results of the CONSENSUS II trial are probably dependent on the excessively abrupt acute hypotensive effect of i.v. enalaprilat. This last "large trial" decade has taught us that many treatments can be advantageous for acute myocardial infarction but, apart from thrombolysis, all other medical therapies should not be given extensively, but to peculiar patients carefully selected on clinical grounds. Guidelines from official consensus conferences are expected now, to segregate different patterns of clinical presentations to be treated differently.

Effects of uridine in the treatment of diabetic neuropathy: an electrophysiological study

The authors performed a controlled double-blind neurophysiological study (uridine vs placebo) in 40 diabetic patients with peripheral neuropathy. Twenty subjects were treated with uridine and 20 with placebo. The neurophysiological evaluation consisted of a study of the MCV of the median nerve, the common Peroneal, the posterior Tibial, the SCV of the radial nerve, the median and the sural as well as the amplitudes of the motor and sensory responses. The nerves examined were on the dominant side. The evaluations were performed at baseline and after 60, 120, 180 days of therapy with a follow up control after 90 days from the completion of therapy. No statistically significant modifications were observed in the placebo group. In the drug group, the neurophysiological parameters improved significantly from the 120th day post therapy compared with baseline and were maintained through to follow up. The authors discuss the results which demonstrated that treatment with uridine can bring about a neurophysiological improvement in peripheral nerves.

Study of the P300 event-related potential through brain mapping in phonological dyslexics

The auditory P300 was studied through brain mapping in 10 phonological dyslexics (7 M and 3 F), who were found to differ significantly from normals in presenting a longer P300 latency and smaller amplitude on the N2-P3 wave. Interesting too was the asymmetry of the P300 distribution between the two hemispheres, with less amplitude on the right. These findings confirm the hypothesis of reduced right hemisphere functioning during the process of information analysis in phonological dyslexics.

Predicting cardiac mortality after uncomplicated myocardial infarction by exercise radionuclide ventriculography and exercise-induced ST segment elevation

In 183 consecutive patients with recent, uncomplicated myocardial infarction, the following variables were associated with 4-year cardiac death: haemodynamic decompensation with exercise (P = 0.01), left ventricular ejection fraction at rest (P = 0.004) and at peak exercise (P = 0.003), persistent ST segment elevation at rest in the area of infarction = (P = 0.004), exercise-induced ST segment elevation (P = 0.02), and late aneurysmal evolution (P = 0.01). Exercise left ventricular ejection fraction was the sole variable selected by Cox regression analysis as an independent predictor of cardiac death. In 40 patients with ST segment elevation at rest, left ventricular ejection fraction was 42 +/- 17% at rest and 40 +/- 18% at peak exercise, versus 52 +/- 12% and 52 +/- 14% in the remaining patients (both P less than 0.01). Among these 40, 16 (all with anterior infarction) also had exercise-induced ST segment elevation; their ejection fraction was 32 +/- 13% at rest, 30 +/- 13% during exercise, versus 53 +/- 15% and 53 +/- 15% in 129 patients with no ST segment elevation either at rest, or during exercise (both P less than 0.01). The 4-year risk of death was 20% in the former 40 patients, 36% in the latter 16, while in the complete absence of ST segment elevation, such risk was 3%. All 14 patients with ST segment elevation only during exercise were alive after 4 years: their left ventricular ejection fraction was 47 +/- 12% at rest, 45 +/- 13% with exercise. ST segment elevation was associated with late aneurysmal evolution but not with exercise-induced ischaemia.(ABSTRACT TRUNCATED AT 250 WORDS)